We've featured a Jacob Palmborg design pretty recently here on SlashGear, but the young designer seems to have a knack for developing tactile, jewel-like concepts that make you ache to hold them. His OLED cellphone was a slick, kinked shard of monochromatic plastic and metal, obviously expensive, and now he's come up with the ideal way to pay for it. Only this being the 21st century, you're likely to get a jugful of guilt along with the purchase.
Instead of credit cards as they are now - unresponsive windows into debt and misery (can you tell I just got my latest statement?) - Jacob's concept is an RFID linked mini-display that not only indicated how much you have in each linked account but, should you spend some of it, gives you a visual forecast on how that might effect your future economic status.
There's also a fingerprint scanner to make sure it's really you using the card. Personally I'd like that scanner to be able to give me electric shocks when it senses that I'm buying something ridiculous that I don't need.